ORCID Profile
0000-0003-4357-6889
Current Organisation
Argonne National Laboratory
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
Publisher: American Chemical Society (ACS)
Date: 06-09-2019
Publisher: The Electrochemical Society
Date: 12-2020
Abstract: The energy density of lithium-ion batteries can be increased by replacing the traditional graphite anode with a high capacity silicon anode. However, volume changes and interfacial instabilities cause a large irreversible capacity and a continual loss of lithium during cycling, which lead to rapid capacity loss. In this work, we add Li 5 FeO 4 (LFO) to a LiNi 0.5 Mn 0.3 Co 0.2 O 2 (NMC) cathode as a pre-lithiation additive, which increases the lithium inventory and extends the cycle life of Si-graphite/NMC full cells, and decreases the NMC particle degradation. LFO delivers a large 764 mAh g −1 LFO capacity below 4.7 V vs Li/Li + . By tuning the LFO content in Si-graphite/LFO-NMC full cells, we show higher capacity, improved retention, lower impedance, and superior rate performance compared to full cells without LFO. Post-test characterizations demonstrate that LFO inclusion in the cathode matrix leads to less NMC secondary particle segregation/cracking and a thinner surface reduced layer on the NMC particles. The beneficial effects of LFO endure after the lithium reserve has been exhausted, highlighting a lasting synergy between the lithium source and electrode active materials. This study introduces a new approach to simultaneously increase lithium inventory and reduce cathode degradation, and makes critical advances toward enabling Si anodes for lithium-ion batteries.
Publisher: American Chemical Society (ACS)
Date: 06-09-2018
Publisher: Springer Science and Business Media LLC
Date: 30-10-2019
DOI: 10.1038/S41467-019-12863-6
Abstract: Due to their exceptional high energy density, lithium-ion batteries are of central importance in many modern electrical devices. A serious limitation, however, is the slow charging rate used to obtain the full capacity. Thus far, there have been no ways to increase the charging rate without losses in energy density and electrochemical performance. Here we show that the charging rate of a cathode can be dramatically increased via interaction with white light. We find that a direct exposure of light to an operating LiMn 2 O 4 cathode during charging leads to a remarkable lowering of the battery charging time by a factor of two or more. This enhancement is enabled by the induction of a microsecond long-lived charge separated state, consisting of Mn 4+ (hole) plus electron. This results in more oxidized metal centers and ejected lithium ions are created under light and with voltage bias. We anticipate that this discovery could pave the way to the development of new fast recharging battery technologies.
Publisher: Elsevier BV
Date: 02-2022
Publisher: The Electrochemical Society
Date: 2018
DOI: 10.1149/2.1271810JES
Publisher: AIP Publishing
Date: 04-2022
DOI: 10.1063/5.0084105
Abstract: The lithium-ion cathode material olivine LiFePO4 (LFP) has been synthesized for the first time from natural paleozoic iron carbonate (FeCO3). The ferrous carbonate starting material consists of the mineral siderite at about 92 wt. % purity. Because FeCO3 has alent iron, the reaction with lithium dihydrogen phosphate (LiH2PO4) provides a unique method to develop iron-(II) containing LFP in an inert atmosphere. Since siderite FeCO3 is a common mineral that can be directly mined, it may, therefore, provide an inexpensive route for the production of LFP. After carbon-coating, the LFP yields a capacity in the range of 80–110 mAh g−1LFP (in one chosen specimen s le), which is lower than commercially available LiFePO4 (150–160 mAh g−1LFP). However, the tap density of LFP derived from siderite is noticeably high at 1.65 g cm−3. The material is likely to be improved with powder purification, nanosized processing, and more complete carbon-coating coverage with increased optimization.
Publisher: American Chemical Society (ACS)
Date: 21-06-2019
Publisher: Royal Society of Chemistry (RSC)
Date: 2018
DOI: 10.1039/C8CC00456K
Abstract: A silicon-graphite blended anode is paired with a high capacity LiFePO 4 reference/counter electrode to track irreversibility and lithium inventory.
Publisher: American Association for the Advancement of Science (AAAS)
Date: 13-05-2022
Abstract: A reliable energy storage ecosystem is imperative for a renewable energy future, and continued research is needed to develop promising rechargeable battery chemistries. To this end, better theoretical and experimental understanding of electrochemical mechanisms and structure-property relationships will allow us to accelerate the development of safer batteries with higher energy densities and longer lifetimes. This Review discusses the interplay between theory and experiment in battery materials research, enabling us to not only uncover hitherto unknown mechanisms but also rationally design more promising electrode and electrolyte materials. We examine specific case studies of theory-guided experimental design in lithium-ion, lithium-metal, sodium-metal, and all-solid-state batteries. We also offer insights into how this framework can be extended to multivalent batteries. To close the loop, we outline recent efforts in coupling machine learning with high-throughput computations and experiments. Last, recommendations for effective collaboration between theorists and experimentalists are provided.
Publisher: Royal Society of Chemistry (RSC)
Date: 2021
DOI: 10.1039/D1TA01290H
Abstract: Over lithiated Li 1+x NMCO 2 is introduced as a dual-functional lithium source and cathode material to increase the lithium inventory and significantly improve the energy density and cycle life of lithium-ion batteries with a Si-based anode.
Publisher: Elsevier BV
Date: 10-2018
No related grants have been discovered for Christopher Johnson.